The present invention generally relates to power distribution systems and more particularly to a system and method of large area microgrid stability controls.
Microgrid power installations are becoming more useful for power surety and security for bases, campuses, industrial facilities, and other collections of high priority electrical loads. These systems are a rapidly growing segment of the power industry. In general, microgrids may be used to manage sources, loads and storage systems to optimize availability, economy, reliability, etc. Sources can vary widely (e.g. utility grid, diesel generators, wind turbines, photovoltaics, gas turbines) and may deliver power as AC or DC. The loads the system supplies can also be AC or DC in nature, and may vary widely in their power requirements and over time. Current microgrids typically cover a small area with a small number of power generation sources or may depend on large central power plants that provide power to the loads in a similar manner that the electric utility company does.
In cases where many electric power generation sources such as backup generators and renewable sources are used, challenges occur with the coordination of the sources and with load management. For example, when a number of generators with controllers are networked and supply power to a common load circuit, changes in loads may cause instability on the grid. The response behavior of different sources to changes in loads may cause oscillations in generator loading that can result in “hunting” behavior and failure of the microgrid.
One approach to prevent instability uses several matched generators with similar behaviors to accommodate loads resulting from different buildings requiring power. However, some buildings may need much more power than others. Thus, to ensure an even distribution of power, some buildings may receive power from a generation source that is much larger and expensive than necessary.
As can be seen, there is a need for managing generators over large areas and which may use many disparate generation sources.